Gratitude Crystal

"Crystallized feelings of pure gratitude. Gather them and show them to Batreaux."

— In-game description.

Gratitude Crystals are items from The Legend of Zelda: Skyward Sword. These crystals are physical manifestations of peoples' feelings of gratitude; there are 80 of them in all, and they may be gained after completing various side-quests for denizens of Skyloft. Gratitude Crystals may be exchanged with Batreaux for several rewards. Humorously, Kukiel refers to them as "grabitude crackles."

Once 80 Gratitude Crystals have been found, Batreaux is transformed into a human and in his own gratitude rewards Link with the Tycoon Wallet, which can hold up to 9,000 Rupees. Furthermore, the transformations that Remlits undergo at night are undone as well, and enemies such as ChuChus and Keese no longer appear in Skyloft at night.